A useful function for detector circuits is the indication or selection of a maximum or minimum value from an input comprising a multiplicity of electrical signals or optical intensity values, such as from a detector array, for example. A commonly used processing technique for determining maximum/minimum values is digitization of the input signal distribution set followed by digital comparison of the elements of the set. An alternative method involves complicated analog feedback circuitry for suppressing non-extreme values of the input set. Because these prior art techniques require complex circuits for manipulating elements of the input set, a simple, straight-forward, analog method has been sought for indicating and/or selecting the maximum or minimum value from a set of input signals.